#!/usr/bin/env python3
"""Turn a generated material picture into a texture for the furniture (props.rs): cropped,
optionally turned into grey detail (the furniture's colours tint it in the game), brightened to
a common mean and scaled to the high-res size and the pixel-art size.

Usage:
  make_material.py raw.png out_prefix [--crop x0,y0,x1,y1] [--trim] [--color] [--mean 0.8]

--crop   fractions of the picture to keep
--trim   crop to the picture's object (everything that is not near-white background)
--color  keep the colours (else grey detail)
--mean   mean brightness of the result (0..1)

Writes out_prefix-64.png and out_prefix-16.png. Needs Pillow.
"""
import argparse

from PIL import Image, ImageOps, ImageStat


def main():
    ap = argparse.ArgumentParser()
    ap.add_argument("raw")
    ap.add_argument("out")
    ap.add_argument("--crop", default=None)
    ap.add_argument("--trim", action="store_true")
    ap.add_argument("--color", action="store_true")
    ap.add_argument("--mean", type=float, default=0.8)
    a = ap.parse_args()

    img = Image.open(a.raw).convert("RGB")
    if a.crop:
        f = [float(v) for v in a.crop.split(",")]
        img = img.crop((int(f[0] * img.width), int(f[1] * img.height), int(f[2] * img.width), int(f[3] * img.height)))
    if a.trim:
        # the object: everything darker than the white background, a few pixels in
        mask = img.convert("L").point(lambda v: 255 if v < 235 else 0)
        box = mask.getbbox()
        if box:
            img = img.crop((box[0] + 4, box[1] + 4, box[2] - 4, box[3] - 4))
    if not a.color:
        img = ImageOps.grayscale(img).convert("RGB")
    mean = ImageStat.Stat(img.convert("L")).mean[0] / 255
    k = a.mean / max(mean, 0.01)
    img = img.point(lambda v: min(255, int(v * k)))
    img.resize((64, 64), Image.LANCZOS).save(f"{a.out}-64.png")
    small = img.resize((16, 16), Image.BOX)
    small.quantize(colors=8, method=Image.Quantize.MEDIANCUT, dither=Image.Dither.NONE).convert("RGB").save(f"{a.out}-16.png")
    print(f"{a.out}-64.png, {a.out}-16.png")


if __name__ == "__main__":
    main()